Wednesday, 24 August 2011

The new Ferrari 458 Spider will feature a retractable hard-top roof when it breaks cover at next month’s Frankfurt motor show. Although Ferrari has already produced a hard-top convertible in the current California, the 458 Spider will be the first time that it has fitted a folding hard roof to a mid-engined two-seater.

The F430 Spider, released in 2005, was given a soft-top to keep weight down, but Ferrari has made the new machine’s roof using lightweight aluminium, which means the whole roof and its mechanism is 25kg lighter than a soft-top’s would be. Ferrari’s figures give a dry weight of 1430kg for the 458 Spider, making it about 50kg heavier than the Italia.

Packaging considerations also dictated Ferrari’s choice of the hard-top, which can be deployed in 14sec. It was engineered to fit ahead of the engine bay without compromising aerodynamics or performance. The smaller space needed to house the roof means that there is space for a luggage bench behind the seats.

The operation of the retractable roof uses a central pivot, as opposed to the hinge system which is more common on cabriolets. A similar system was used on the Ferrari 575 Superamerica. On the 458 Spider, the buttresses behind each seat are designed to optimise the flow of air to the engine intakes and the clutch and gearbox oil radiators.

The Spider uses the same 4.5-litre, 578bhp, 55kgm V8 powerplant as the 458 Italia. The throttle pedal mapping and multi-link suspension’s damping have been calibrated specifically for this version, and the engine note has been tuned for top-down driving. An electric wind stop is fitted to reduce noise when the roof is retracted, and normal conversation can be sustained at more than 194kph.

Despite the extra weight, the convertible retains the 0-100kph time of under 3.4sec that the 458 Italia has. Top speed will be around 318kph, compared with the 458 Italia’s 325kph.